A previous device for circulatory support is known from U.S. Pat. No. 5,749,855, having the same inventor as the present invention. The device comprises a drive cable, with one end of the drive cable being connectable to a drive source and a collapsible drive propeller at the other end of the drive cable. The collapsible drive propeller is adjustable between a closed configuration in which the collapsible drive propeller is collapsed on the drive cable and an open configuration in which the collapsible drive propeller is expanded so as to be operative as an impeller. A sleeve extends between one side of the collapsible drive propeller and the other side of the collapsible drive propeller with the sleeve being movable between configurations in which the collapsible drive propeller is in the open and closed configuration. A lattice cage is arranged surrounding the propeller and is folded out at the same time as the propeller.
This device operates very well in many circumstances. However, there is still room for improvements. For example, it would be safer if the lattice cage is folded out before the propeller is folded out. In addition, the shaft supporting the propeller needs to be journalled with bearings, and such bearings need to be lubricated.
Other catheter pumps are known from US 2008/0132748 A1, US 2008/0114339 A1 or WO03/103745A2.